DNS and Laser Diagnostics of Steam-Diluted Hydrogen-Oxygen Combustion for Future Electric Power Generation
Department of Mechanical Engineering,
Tokyo Institute of Technology, Japan
Direct numerical simulation (DNS) and laser diagnostics of turbulent combustion has been strong research tools in the combustion society. Recently, DNS of turbulent combustion was extended for investigations on important phenomena in engineering applications such as high Karlovitz number flame, HCCI combustion, ignition in turbulence, flame-wall interaction, etc. For the laser diagnostics, high-speed particle image velocimetry (PIV) and high-speed planar laser induced fluorescence (PLIF) of OH, CH and CH2O are available now. In this talk, after showing the progresses in DNS and laser diagnostics of turbulent combustion in the last two decades, a new application of these techniques is presented for investigation on steam-diluted hydrogen-oxygen combustion. The steam-diluted hydrogen-oxygen combustion will be used for the future electric power generation which is working toward practical use around 2050 in Japan. In this power generation system, since only hydrogen and oxygen are used with circulating high pressure and high temperature steam, zero emission (no CO2 and no NOx) will be achieved with high thermal efficiency. To realize the semi-closed cycle based on the hydrogen-oxygen combustion, detailed investigation on flame structure of steam-diluted hydrogen-oxygen turbulent flame is required. In this study, DNS approach is applied to understand the flame structure in specially-designed multi-cluster burner. Simultaneous high-speed PIV and OH PLIF is also applied for the model combustor. DNS and high-speed laser diagnostics give lots of important information on the mixing and combustion characteristics in the cluster burner, which is successfully applied to improvement of burner design.